The rising sun painted the snow of Mount Sagiri in brilliant hues of orange and pink. It was a scene of breathtaking beauty, peaceful and serene.
It stood in stark contrast to the man stumbling out of the tree line.
Su Chen looked like he had wrestled a bear and lost. His pajamas were torn to shreds, revealing bruised skin that was already fading from purple to yellow—a testament to his newly acquired [Lesser Regeneration].
The magazine armor on his arms hung in tatters, flapping in the wind.
But he was alive. And he was smiling.
At the foot of the mountain, near the small hut, a young boy with burgundy hair was pacing anxiously. When he saw Su Chen, his face lit up.
"Su Chen-san!" Tanjiro cried out, running forward. "You're alive! You actually made it back!"
Tanjiro stopped just short of hugging him, his nose twitching.
"You smell like..." Tanjiro paused, his expression confusing. "Old blood? And... ash?"
The door to the hut slid open. Urokodaki stepped out. He was holding a pot of steaming soup, but he set it down on the wooden porch when he saw Su Chen.
The old man walked over, his steps silent on the snow. He stood in front of Su Chen, the red tengu mask unreadable.
"You killed a demon," Urokodaki stated. It wasn't a question.
Su Chen nodded, leaning heavily on his battered frying pan. "A straggler. Weak. But it didn't like the sun."
Urokodaki stared at the frying pan, noting the deep claw marks in the cheap iron. Then he looked at Su Chen's hands—no sword calluses, no warrior's grip. Just a civilian who used the environment to survive.
"Resourceful," Urokodaki grunted. "And lucky. Most die on their first night."
"Does this mean you'll teach me?" Su Chen asked, straightening his back.
"I said I would," Urokodaki turned back to the hut. "Come inside. Eat. Then, you pick up a sword."
The interior of the hut was warm. A fire crackled in the irori (sunken hearth). In the corner, a futon was laid out where a girl with a bamboo muzzle lay sleeping deeply—Nezuko.
Su Chen glanced at her.
[Target: Kamado Nezuko (Demon/Dormant)]
[Status: Evolving]
[Copyable Attributes:]
Demonic Blood Art: Exploding Blood (Locked)
Size Manipulation (Locked)
Solar Immunity (Developing - 15%)
Not yet, Su Chen thought, withdrawing his gaze. If I touch her now, Urokodaki will chop my head off. Building trust comes first.
He sat down with Tanjiro. Urokodaki served them bowls of vegetable soup with mountain yams.
Su Chen took a sip. It was bland, but hot.
"System," Su Chen subvocalized. "Access Storage."
Under the cover of the table, he materialized a small chunk of the Tier-1 Wolf Meat (cooked version from Earth) into his hand and dropped it into his soup.
The broth immediately turned richer, glistening with energy.
He ate the wolf meat.
Boom.
A rush of heat exploded in his stomach. The high-energy protein from the mutated Earth beast was like rocket fuel for a normal human body.
[System Notice: High-Grade Protein ingested.]
[Passive 'Lesser Regeneration' accelerated by 300%.]
[Experience +10]
His bruises vanished visibly. His fatigue melted away.
Tanjiro, sitting next to him, sniffed the air again. "Su Chen-san... your soup smells really... powerful?"
"Secret family recipe spice," Su Chen whispered, winking. "I'll give you some later."
An hour later. The clearing outside the hut.
"The sword is the extension of your arm,"
Urokodaki announced. He held a wooden practice sword (bokken). "But a sword without breath is just a metal stick. To fight demons, you must master Total Concentration Breathing."
Su Chen stood next to Tanjiro. Both of them held wooden swords.
"Listen to your lungs," Urokodaki instructed.
"Expand them. Force the oxygen into every cell. Let the blood flow increase. Let your body heat rise."
Urokodaki demonstrated. He stood perfectly still, but the air around him seemed to vibrate. A faint sound of rushing water echoed, though there was no river nearby.
Swish!
Urokodaki swung his sword. It was a simple vertical slash, but it carried enough force to create a gust of wind that blew the snow off a nearby branch.
"This is the First Form of Water Breathing: Water Surface Slash," Urokodaki said. "Now, try."
Tanjiro closed his eyes, struggling to mimic the breathing rhythm.
Su Chen didn't close his eyes. He walked up to Urokodaki.
"Master," Su Chen said politely. "My grip is wrong. Can you correct it?"
Urokodaki sighed at the novice request but reached out and adjusted Su Chen's hands on the hilt.
Contact confirmed.
[Target: Urokodaki Sakonji (Former Water Hashira)]
[Copyable Attributes Detected:]
Water Breathing Technique (Mastery: Grandmaster)
Swordsmanship Insight (Passive)
Instructional Aura (Buffs students nearby)
"Copy: Water Breathing Technique."
Buzz.
A massive influx of information flooded Su Chen's brain.
It wasn't just words. It was the sensation of air moving through alveoli. It was the specific rhythm of the heart. It was the visualization of water flowing through veins. It was the muscle memory of ten thousand swings.
[Skill Acquired: Water Breathing (Style)]
[Current Proficiency: Novice (1/1000)]
[Warning: Host's physique is insufficient to utilize full power. Forced usage may result in lung damage.]
Su Chen stepped back, his eyes gleaming.
He had the software installed. Now he just needed to upgrade the hardware.
He closed his eyes. He didn't need to guess the rhythm like Tanjiro. He knew it. He accessed the memory he had just stolen.
Inhale.
Skreee...
A sharp, whistling sound came from Su Chen's mouth.
Tanjiro's eyes widened. "That sound... it's just like Urokodaki-san's!"
Su Chen felt his lungs burning. It felt like he was inhaling fire. His blood vessels expanded, throbbing against his skin. His Strength stat temporarily jumped from 9.1 to 12.
"First Form..." Su Chen whispered, raising the wooden sword.
He visualized the water.
Slash!
The wooden sword cut through the air.
Crack!
The bokken snapped in half upon hitting the empty air? No—Su Chen had swung it with too much erratic force, and his wrist had twisted wrong, causing the wood to fracture against his own inconsistent momentum.
"Gah!" Su Chen dropped the broken handle, clutching his chest. He coughed violently, tasting copper.
[System Warning: Lung Tissue strained. Minor internal bleeding.]
[Lesser Regeneration activating...]
Urokodaki stared at him, genuinely shocked.
"You..." The old man stepped forward. "You achieved the breathing rhythm on your first try? But your body is too weak to hold it."
"I... cough... I'm a quick learner," Su Chen wheezed, wiping blood from his lip. "But my body is garbage."
"Correct," Urokodaki said sternly, though his tone held a hint of awe. "You have the instinct of a genius, but the body of a sickly child. If you use that breathing again before your muscles are ready, your veins will burst."
Su Chen grinned, his teeth stained red.
"Then we train the body."
The Montage: Day 1 to Day 15.
The training regimen was brutal.
Every day, they ran down the mountain.
Every night, they climbed back up.
Tanjiro struggled with the traps. Su Chen sniffed them out with [Olfactory Sense] but purposely triggered some to toughen his skin, relying on his [Regeneration] to heal him overnight.
But Su Chen had a secret weapon.
While Tanjiro slept, Su Chen would sneak out to the back of the hut.
[Infinite Storage: Open.]
He pulled out the Tier-1 Wolf Meat. He ate it raw or seared over a small magical fire.
The nutrient density of the Expanded Earth monsters was hundreds of times higher than the rice and soup of the Taisho era.
Day 3:
Su Chen copies [Hard Skull] from Tanjiro.
[Constitution: 7 -> 8.5]
Day 7:
Su Chen continuously copies the [High Oxygen Atmosphere] of the mountain and releases it inside his own lungs using a micro-portal trick, forcing his cells to adapt faster.
[Strength: 9.1 -> 11]
Day 12:
Su Chen asks to spar with Sabito (the ghost boy who appeared to Tanjiro).
Su Chen can't see ghosts yet. But he can smell them.
"You smell like sorrow," Su Chen said to the empty air in the clearing.
Whack!
An invisible wooden sword hit him in the face.
"I can hit you, but I can't copy you if you're intangible," Su Chen grumbled, rubbing his cheek. "Wait... System, is a ghost a target?"
[Target: Sabito (Spirit Remnant)]
[Copyable Attribute: Spirit Presence (Allows interaction with spiritual bodies)]
"Copy."
Suddenly, the empty air shimmered. A boy with peach-colored hair and a fox mask faded into view.
Sabito looked surprised. "You... you can see me?"
"I can do more than that," Su Chen raised his wooden sword. "I can learn from you."
Day 30.
Su Chen stood at the top of the waterfall. He was shirtless. His body, once thin and average, was now lean and wired with dense muscle.
[Status Update]
Name: Su Chen
Level: 2 (150/200 EXP)
Strength: 14 (Elite Athlete level)
Agility: 13
Constitution: 15 (Enhanced Recovery)
Spirit: 18
Skills:
[Water Breathing (Proficiency: Intermediate)]
[Total Concentration: Constant (Work in Progress - 10%)]
[Swordsmanship (Basic -> Intermediate)]
[Spirit Sight]
He took a deep breath.
Whoosh.
The air didn't whistle anymore. It roared low and deep, like a tide coming in.
He drew a real steel katana (one he had "borrowed" and copied from Urokodaki's rack).
"Water Breathing, Second Form: Water Wheel."
Su Chen leaped. His body spun in a perfect vertical circle. The blade trailed a phantom stream of blue water—the visual manifestation of high-density spirit energy.
Slash!
The massive bamboo stalk in front of him was severed cleanly.
"Not enough," Su Chen landed softly. "This is enough to kill a normal demon. But compared to the monsters back on Earth... this is just the beginning."
He looked at the countdown timer on his System Panel.
[Time Spent in World: 30 Days.]
[Time Passed on Earth: 24 Hours.]
"Tomorrow, the Final Selection begins for Tanjiro's timeline," Su Chen mused. "But I don't need to go to the Final Selection to get a rank. I'm a traveler."
However, he remembered the [Hand Demon] at the Final Selection.
A massive, morphed demon that had eaten fifty kids.
[Target Potential: Hand Demon]
[Estimated Drops: Mutated Demon Arm (material), Mid-Grade Vitality Orb, 500 EXP.]
Su Chen sheathed his sword. A cold, greedy light flickered in his eyes.
"That Demon has a lot of biomass. If I feed it to my System..."
"Tanjiro!" Su Chen yelled down the mountain. "Pack your bags! We're going to the Wisteria Mountain!"